Synapse & synaptic plasticity Flashcards
Define a synapse transmission
When neural impulses reaches the end of each axon, terminal buttons release chemicals called neurotransmitters
Define neural plasticity
Neural plasticity refers to the idea that the brain constantly changes throughout the lifespan
Define neuroplasticity
The brains ability to change itself as a result of experience
Define developmental plasticity
Natural occurrence of certain critical periods of greater developmental plasticity
Define adaptive plasticity
Occurs as a result of brain dammage or trauma; utilizing critical periods for developmental plasticity helps enable greater adaptive plasticity
Define synaptic plasticity
Neuroplasticity of a single cell level (Only between neurons), the ability of synaptic connection to change over time in response to activity or experience
Define long term potentiation (LTP)
An experience-dependent increase in synaptic strength through high frequency simulation of neural pathways; strengthening of synaptic connections that are regularly activated
What are the structural changes for LTP?
- Increase in receptor sites
- Increase in release of glutamate
- Synaptogenesis (When new synapses are made, aka sprouting) is occurring
Define long term depression (LTD)
Experience-dependent weakening of synaptic connection between neurons that are not regularly activated (as a result of simulation of pre & post synaptic neurons
What are the structural changes for LTD?
- decrease in receptor sites
- less glutamate is released
What is the functional change of LTD?
The post-synaptic neuron is less likely to fire (less action potential)
Why is LTD important?
The removal of unused/unnecessary synapses & makes learning and memory process more efficient
Define sprouting
Creation of new connections between neurons through the growth at axon and/or dendrite fibers at the synapse
What are changes that happen when sprouting occurs?
- Growth of dendritic spines on post-synaptic neuron
- Growth of axon sprouts (filigree appendages) on pre-synaptic neuron
- Formation of additional synapses (dendric spines and filigree appendages meet) known as synaptogenesis
Define rerouting
Re-establishing neural connections by creating alternate pathways (Also occurs between damaged neurons to created alt synapse connections)
When does rerouting occur?
- As a result of LTD, so an alternate pathway associated to the behavior can be formed
Define pruning
Removing old neural connections that are not adequately activated regularly & makes communication between neurons more direct
When does pruning often occur?
LTD, it often includes some pruning in order to increase efficiency of neural transmission
